Branches Dashboard: Hide branches that have been merged

In the Branches Dashboard add-on, I can see all the branches in my project, which is fantastic. However, our workflow requires that we not delete branches when we're done with them, for traceability purposes. This means that the branches dashboard is littered with branches that have been merged, and are thus of no interest on this dashboard.

Is is possible to hide branches that have been merged, on this dashboard?